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Effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization in high myopia mice 被引量:2
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作者 Yan-Yan Ji Shi-Xi Zhang +1 位作者 Ye Kang Song Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第7期1034-1040,共7页
AIM:To evaluate effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization(CNV)in high myopia mice.METHODS:The C57BL/6J mice were deprived of the right eye for 4wk,a... AIM:To evaluate effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization(CNV)in high myopia mice.METHODS:The C57BL/6J mice were deprived of the right eye for 4wk,and the high myopia was diagnosed by optometry,the diopter was less than-6.00 D,and CNV was induced by 532 nm laser.The changes of dopamine D1 receptor(DRD1),dopamine D2 receptor(DRD2),and vascular endothelial growth factor A(VEGFA)were detected by Western blot technology at 0.5,1,2h,and 7d after 0.01%,0.05%,and 0.1%atropine eye drops,respectively,the area of CNV was measured.RESULTS:Significant increases were observed on the expression of DRD2 in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).Significant decreases were observed on the expression of DRD1 and VEGFA in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).The area of CNV induced by laser in the drug-treated group was significantly smaller than that in the control group,and the higher the concentration,the more significant the inhibitory effect(P<0.05).CONCLUSION:The 0.01%,0.05%,0.1%atropine eye drops can decrease the level of VEGFA and inhibit high myopia CNV indirectly by up-regulating the level of DRD2 and down-regulating the level of DRD1,and the effect of 0.05%and 0.1%atropine eye drops is more significant. 展开更多
关键词 high myopia choroidal neovascularization low concentration atropine eye drops dopamine D1 receptor dopamine D2 receptor
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Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees,Following in vivo Injection of very Low Doses 被引量:1
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作者 K.M'DIAYE M.BOUNIAS 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1993年第2期145-153,共9页
The injection to emerging adult workerbees with fluvalinate doses ranging from 1 femtomol to 1 nanomol per individual resulted in a reduction of haemolymph carbohydrate concentrations, particularly at the lowest dose ... The injection to emerging adult workerbees with fluvalinate doses ranging from 1 femtomol to 1 nanomol per individual resulted in a reduction of haemolymph carbohydrate concentrations, particularly at the lowest dose 1 hour after injections. At the same time, a large increase was observed for triacylglycerols and to a much lesser extent for steroids and phospholipids with 0.1 picomol per bee. By contrast, fatty acids, steroids and triacylglycerols exhibited a depress at the higher dose. Most responses were thus biphasic, showing that much attention should be paid to the effects of very low doses of pesticide. 展开更多
关键词 Time and Dose-related Effects of the Pyrethroid Fluvalinate on Haemolymph Carbohydrates and Gut Lipids of Honeybees Following in vivo Injection of very low doses very
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Usefulness of anti-ulcer drugs for the prevention and treatment of peptic ulcers induced by low doses of aspirin 被引量:11
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作者 Sayaka Nakashima Shinichi Ota +7 位作者 Shin Arai Kiyoko Yoshino Mie Inao Keiko Ishikawa Nobuaki Nakayama Yukinori Imai Sumiko Nagoshi Satoshi Mochida 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第6期727-731,共5页
AIM:To investigate the usefulness of anti-ulcer drugs for the prevention and treatment of low-dose aspirin- induced peptic ulcer. METHODS:Upper gastrointestinal endoscopy was performed in 68 patients receiving daily l... AIM:To investigate the usefulness of anti-ulcer drugs for the prevention and treatment of low-dose aspirin- induced peptic ulcer. METHODS:Upper gastrointestinal endoscopy was performed in 68 patients receiving daily low-dose aspirin(81 or 100 mg/day).The endoscopic findings were classified according to the Lanza score,and the scores were compared between groups categorized according to the concomitant use of anti-ulcer drugs and the types of drugs used.In another study,31 hemorrhagic peptic ulcer patients who had been receiving low-dose aspirin were enrolled.The patients were randomly classified into the proton pump inhibitor (PPI)-treated group and the H2 receptor antagonist (H2RA)-treated group.The administration of low-dose aspirin was continued concomitantly,and endoscopic examinations were performed 8 wk later. RESULTS:The Lanza scores(mean±SD)of the gastro-mucosal lesions were 1.0±1.9 and 1.9±2.3 in 8 and 16 patients receiving prevention therapy with a PPI and an H2RA,respectively.Both scores were significantly smaller than the scores in 34 patients who were not receiving prevention therapy(4.7±1.0)and in 10 patients receiving cytoprotective anti-ulcer drugs (4.3±1.6).In the prospective study,18 and 13 patients received a PPI and an H2RA,respectively.Endoscopic examinations revealed that the tissue in the region of the gastro-mucosal lesions had reverted to normal in all patients in the PPI-treated group and in 12 patients (92%)in the H2RA-treated group;no significant differences were observed between the groups. CONCLUSION:H2RA therapy was effective for both the prevention and treatment of low-dose aspirin- induced peptic ulcer,similar to the effects of PPIs, while cytoprotective anti-ulcer drugs were ineffective in preventing ulceration. 展开更多
关键词 消化系统 溃疡 低剂量阿司匹林 抑制剂
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Reaction of water and living systems under the chronic effect of ionized radiation in low doses
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作者 Igor Borisovich Ushakov Vladimir Vladimirovich Tsetlin Svetlana Stepanovna Moisa 《Journal of Biomedical Science and Engineering》 2012年第12期771-778,共8页
It is represented the review about the effect of low doses of ionized radiation on different types of biological objects (Japanese quail embryos, Aspergillus niger, Spirostomum ambiguum Ehrbg., mezenchim stem cells of... It is represented the review about the effect of low doses of ionized radiation on different types of biological objects (Japanese quail embryos, Aspergillus niger, Spirostomum ambiguum Ehrbg., mezenchim stem cells of mice bone brain, dry seeds of the highest plants, blood lymphocytes of pilots and cosmonauts) and water medium. In model experiments under the chronic ionized radiation in doses comparable with the doses of ionized radiation inside the orbital space stations and during the flight in interplanetary space was shown alike with morphological deviations (Japanese quail embryos, Aspergillus niger), the phenomenon of radiation hormezis (Aspergillus niger, mezenchim stem cells), the increasing of the germination of seeds, the decreasing of spontaneous motion activity of spirostoms and DNA damage, chromosome aberrations and the increased radio-sensitivity to adding radiation load in blood lymphocytes. These data testified the fact that the definite factor of ionized radiation effect is the changing of water medium state. Thus under the interplanetary cosmic flight and long stay on the orbit in the region of magnetosphere the studying kinds of radiation first effected on the water medium of organism as a result morpho-functional structures were changed. 展开更多
关键词 Ionized RADIATION REACTION of Water LIVING Systems low doses ORBITAL SPACE STATION
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Atropine eye-drop-induced acute delirium:a case report 被引量:1
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作者 Prashant Maravi Dheerendra Kumar Mishra +1 位作者 Amrendra Singh Vijay Niranjan 《General Psychiatry》 CSCD 2020年第3期197-198,共2页
Atropine is an anticholinergic drug which is used in both parental and topical routes.Topical eye-drops of atropine sulfate are used as mydriatic and cycloplegics.Parental atropine-induced delirium is well known but t... Atropine is an anticholinergic drug which is used in both parental and topical routes.Topical eye-drops of atropine sulfate are used as mydriatic and cycloplegics.Parental atropine-induced delirium is well known but topical atropine eye-drop-induced delirium cases are very limited in literature.In this case report,an elderly man underwent cataract surgery and developed delirium after the use of 1%atropine sulfate eye-drops as prescribed.This case supports the notion that even atropine eye-drops can cause delirium in patients at therapeutic doses in elderly. 展开更多
关键词 doses atropine CATARACT
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Ameliorating Effects of Thyroxine and Atropine in Phosphamidon Intoxicated Chick Embryos
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作者 CHATTALI GHOSH AND J.N.MEDDA (Department of Zoology, Burdwan University, Burdwan 713104,West Bengal, INDIA)J.N.MEDDA (To whom all corespondences should be addressed.E-mail:zoojnm@burdwan.ernet.in.) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第1期34-42,共9页
The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average ... The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average body weights, and cholinesterase activity in chick embryos. When thyroxine was administered to the phosphamidon intoxicated embryos, the above parameters changedsignificantly, indicating an ameliorating effect of thyroxine against phosphamidon intoxication in chick embryos. The combined thyroxine and atropine therapy did not further improve the ameliorating effect. Since in many respects chick embryo development parallels that of mammalian embryos,a short-term use of thyroxine as a protective agent against organophosphate toxicity might be useful 展开更多
关键词 ANIMALS atropine Body Weight Central Nervous System Chick Embryo Cholinesterase Inhibitors CHOLINESTERASES Dose-Response Relationship Drug INSECTICIDES Kidney Liver Phosphamidon THYROXINE
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Establishment of NaLuF_(4):15%Tb-based low dose X-PDT agent and its application on efficient antitumor therapy
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作者 Yi Tian Zhiguang Fu +7 位作者 Xiaosheng Zhu Chunjing Zhan Jinwei Hu Li Fan Chaojun Song Qian Yang Yu Wang Mei Shi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期599-610,共12页
X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.Howev... X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.However,high X-ray irradiation dose caused organ lesions and side effects became the major barrier to X-PDT application.To address this issue,this work employed a classic-al co-precipitation reaction to synthesize NaLuF_(4):15%Tb^(3+)(NLF)with an average particle size of(23.48±0.91)nm,which was then coupled with the photosensitizer merocyanine 540(MC540)to form the X-PDT system NLF-MC540 with high production of singlet oxygen.The system could induce antitumor efficacy to about 24%in relative low dose X-ray irradiation range(0.1-0.3 Gy).In vivo,when NLF-MC540 irradiated by 0.1 Gy X-ray,the tumor inhibition percentage reached 89.5%±5.7%.The therapeutic mechanism of low dose X-PDT was found.A significant increase of neutrophils in serum was found on the third day after X-PDT.By immunohistochemical staining of tumor sections,the Ly6G^(+),CD8^(+),and CD11c^(+)cells infiltrated in the tumor microenvironment were studied.Utilizing the bilat-eral tumor model,the NLF-MC540 with 0.1 Gy X-ray irradiation could inhibit both the primary tumor and the distant tumor growth.De-tected by enzyme linked immunosorbent assay(ELISA),two cytokines IFN-γand TNF-αin serum were upregulated 7 and 6 times than negative control,respectively.Detected by enzyme linked immune spot assay(ELISPOT),the number of immune cells attributable to the IFN-γand TNF-αlevels in the group of low dose X-PDT were 14 and 6 times greater than that in the negative control group,respectively.Thus,it conclude that low dose X-PDT system could successfully upregulate the levels of immune cells,stimulate the secretion of cy-tokines(especially IFN-γand TNF-α),activate antitumor immunity,and finally inhibit colon tumor growth. 展开更多
关键词 X-ray excited photodynamic therapy singlet oxygen low dose X-Ray irradiation efficient antitumor therapy anti-tumor immunity
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EPIGENETIC NATURE OF RADIATION CARCINOGENESIS AT LOW DOSES 被引量:4
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作者 T. Sugahara and M. WatanabeHealth Research Foundation. Pasteur Building 5F. 103-5 Tanaka Monzencho. Sakyo-ku. Kyoto 606. JapanFaculty of Pharmaceutical Sciences. Nagasaki University. 1-14 Bunkyo-machi, Nagasaki 852, Japan 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第6期7-12,共6页
The present paradigm of radiation-induced carcinogenesis has been based on somatic mutation theory initiating a mutation in somatic cells derived from DNA damage by ionizing radiation. A non-threshold linear model has... The present paradigm of radiation-induced carcinogenesis has been based on somatic mutation theory initiating a mutation in somatic cells derived from DNA damage by ionizing radiation. A non-threshold linear model has been assumed from high doses to low doses. As an alternative to this, we are proposing a new model that epigenetic changes induced by low dose irradiation may be a first step of carcinogenesis. Our preliminary data suggesting the epigenetic nature and reports on various stress response to ionizing radiation are presented. 展开更多
关键词 In AT EPIGENETIC NATURE OF RADIATION CARCINOGENESIS AT low doses RES
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Variant Wasserstein Generative Adversarial Network Applied on Low Dose CT Image Denoising
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作者 Anoud A.Mahmoud Hanaa A.Sayed Sara S.Mohamed 《Computers, Materials & Continua》 SCIE EI 2023年第5期4535-4552,共18页
Computed Tomography(CT)images have been extensively employed in disease diagnosis and treatment,causing a huge concern over the dose of radiation to which patients are exposed.Increasing the radiation dose to get a be... Computed Tomography(CT)images have been extensively employed in disease diagnosis and treatment,causing a huge concern over the dose of radiation to which patients are exposed.Increasing the radiation dose to get a better image may lead to the development of genetic disorders and cancer in the patients;on the other hand,decreasing it by using a Low-Dose CT(LDCT)image may cause more noise and increased artifacts,which can compromise the diagnosis.So,image reconstruction from LDCT image data is necessary to improve radiologists’judgment and confidence.This study proposed three novel models for denoising LDCT images based on Wasserstein Generative Adversarial Network(WGAN).They were incorporated with different loss functions,including Visual Geometry Group(VGG),Structural Similarity Loss(SSIM),and Structurally Sensitive Loss(SSL),to reduce noise and preserve important information on LDCT images and investigate the effect of different types of loss functions.Furthermore,experiments have been conducted on the Graphical Processing Unit(GPU)and Central Processing Unit(CPU)to compare the performance of the proposed models.The results demonstrated that images from the proposed WGAN-SSIM,WGAN-VGG-SSIM,and WGAN-VGG-SSL were denoised better than those from state-of-the-art models(WGAN,WGAN-VGG,and SMGAN)and converged to a stable equilibrium compared with WGAN and WGAN-VGG.The proposed models are effective in reducing noise,suppressing artifacts,and maintaining informative structure and texture details,especially WGAN-VGG-SSL which achieved a high peak-signalto-noise ratio(PNSR)on both GPU(26.1336)and CPU(25.8270).The average accuracy of WGAN-VGG-SSL outperformed that of the state-ofthe-art methods by 1 percent.Experiments prove that theWGAN-VGG-SSL is more stable than the other models on both GPU and CPU. 展开更多
关键词 Machine learning deep learning image denoising low dose CT loss function
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Effect of low dose laser cycloplasty on deepening anterior chamber in chronic angle-closure glaucoma
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作者 Xuan-Li Zheng Hai-Shuang Lin +4 位作者 Xiao-Jie Wang Jia-Qian Li Yan-Qian Xie Shao-Dan Zhang Yuan-Bo Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2011-2017,共7页
AIM:To describe the outcome of using low-dose laser cycloplasty(LCP)in chronic angle-closure glaucoma(CACG).METHODS:A retrospective case series.Medical charts of CACG patients who underwent LCP in the Eye Hospital of ... AIM:To describe the outcome of using low-dose laser cycloplasty(LCP)in chronic angle-closure glaucoma(CACG).METHODS:A retrospective case series.Medical charts of CACG patients who underwent LCP in the Eye Hospital of Wenzhou Medical University were reviewed.The main outcomes included intraocular pressure(IOP),the number of glaucoma medication,anterior segment parameters and surgery-related complications.RESULTS:A total of 7 eyes of 7 CACG patients(age 38.9±11.0y)underwent LCP with a mean follow-up of 27.1±13.7mo(range 16-48mo).Following LCP,mean IOP and glaucoma medications decreased from 26.1±6.1 mm Hg with 3.1±1.1 glaucoma medications pre-treatment to 14.9±3.1 mm Hg(P=0.027)with 0.4±1.1 glaucoma medications(P=0.001)at final follow-up.The anterior chamber depth(ACD),angle opening distance500 and trabecular-iris angle increased from 1.65±0.33 mm,0.05 mm(range 0-0.30 mm)and 5.1°(range,0-31.97°)at baseline to 1.98±0.43 mm(P=0.073),0.53 mm(range 0.42-0.91 mm,P=0.015),45.9°(range,40.2°-59.4°),(P=0.015)in the long-term follow-up,respectively.The deepening of ACD and reopening of anterior chamber angle(ACA)was observed in 6 eyes(85.7%).CONCLUSION:LCP is a promising treatment option for patients with CACG via reducing IOP and glaucoma medication without serious complications.In addition,LCP can bring a significant deepening in ACD and reopening of ACA. 展开更多
关键词 chronic angle-closure glaucoma low dose laser cycloplasty anterior chamber depth intraocular pressure
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Efficacy of Low Dose Naltrexone on Pain Reduction in Chronic Pain Syndromes: A Meta Analysis
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作者 Haroutiun Hamzoian Shehzad Choudry 《Pain Studies and Treatment》 2023年第3期15-25,共11页
Chronic pain is a multifaceted debilitating experience often associated with significant physical and emotional burden. Low dose naltrexone (LDN) has gained attention in recent years for its potential utility in the m... Chronic pain is a multifaceted debilitating experience often associated with significant physical and emotional burden. Low dose naltrexone (LDN) has gained attention in recent years for its potential utility in the management of fibromyalgia, irritable bowel syndrome, multiple sclerosis, and painful diabetic neuropathy. LDN’s analgesic effects have been associated with its ability to increase the production of endorphins while reducing the production of tumor necrosis factor-alpha, interleukin-6, reactive oxygen species and nitric oxide. This meta-analysis aims to systematically review and synthesize the available evidence on efficacy of LDN as an analgesic in pain syndromes, with a focus on chronic (neuro) inflammatory diseases. The goal is to provide clinicians with a more comprehensive estimate of the effectiveness of LDN as a non-opioid option for managing chronic pain and guide future research in the area. Thirteen randomized control trials, published from 1990 to 2022, were selected for the analysis that satisfied inclusion criteria. The overall effects in these studies were calculated using the standardized mean difference (SMD) between the LDN and placebo groups. We found an overall SMD of -10.77 (95% CI: -13.96 to -7.58) with a p-value of 0.002. This indicated that the LDN group experienced a statistically significant reduction in pain compared to placebo. This meta-analysis provides evidence for the potential efficacy of low dose naltrexone in reducing pain and enhancing analgesia in various pain syndromes. LDN may be a useful treatment option for patients suffering from chronic pain, particularly with fibromyalgia, multiple sclerosis, or diabetic neuropathy. However, further research is needed to confirm the efficacy and safety of low dose naltrexone for chronic pain conditions, especially with larger sample sizes, standardized dosing regimens and treatment durations. 展开更多
关键词 Pain Management LDN PAIN ANESTHESIOLOGY NEUROLOGY low Dose Naltrexone Chronic Pain
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Effective Dose Screening of Low Level Red Light in Different Cell Indexes
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作者 Qiu Shuting Pan Zhi +3 位作者 Jiang Xiao Hu Fan Zhang Hao Wu Fengjuan 《China Detergent & Cosmetics》 CAS 2023年第3期41-50,共10页
The low level red light irradiation dose that produced positive response on different cell indexes was selected through experiments.In fibroblast detection model,the low level red light irradiation dose that had posit... The low level red light irradiation dose that produced positive response on different cell indexes was selected through experiments.In fibroblast detection model,the low level red light irradiation dose that had positive response to the four indicators of mitochondrial membrane potential,ATP release,cell migration and collagen synthesis was screened.The experimental results showed that low level red light with a irradiation dose of 2 J/cm^(2) had a positive response to the above four indexes in fibroblast.The test model on fibroblast was later transferred to dermal papilla cells for further experimental verification.The results showed that low level red light with a irradiation dose of 2 J/cm^(2) also had a positive response to the four indicators of dermal papilla cells,namely,mitochondrial membrane potential,ATP release,cell proliferation rate and collagen synthesis.It is proved that the low level red light with a irradiation dose of 2 J/cm^(2) could improve the mitochondrial function,cell migration and collagen synthesis of fibroblast and dermal papilla cell,thus providing energy for cell activities,improving cell repair ability and cell anti-aging ability. 展开更多
关键词 low level red light dose screening mitochondrial function collagen synthesis cell migration
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丙泊酚复合低剂量艾司氯胺酮应用于无痛超声支气管镜检查的效果 被引量:1
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作者 李璐 周俊飞 +2 位作者 张乐 赫阳森 吕蕴琦 《郑州大学学报(医学版)》 CAS 北大核心 2024年第1期117-120,共4页
目的:评估丙泊酚复合低剂量艾司氯胺酮应用于无痛超声支气管镜(EBUS)检查的效果。方法:纳入2022年4月至8月在郑州大学第一附属医院行无痛EBUS检查的96例患者(年龄18~65岁,BMI 18.5~28.0 kg/m^(2),ASAⅡ或Ⅲ级),随机分为艾司氯胺酮组和... 目的:评估丙泊酚复合低剂量艾司氯胺酮应用于无痛超声支气管镜(EBUS)检查的效果。方法:纳入2022年4月至8月在郑州大学第一附属医院行无痛EBUS检查的96例患者(年龄18~65岁,BMI 18.5~28.0 kg/m^(2),ASAⅡ或Ⅲ级),随机分为艾司氯胺酮组和对照组,每组48例。对照组麻醉诱导方案为丙泊酚1.5 mg/kg+阿芬太尼30μg/kg+米库氯铵0.15 mg/kg,艾司氯胺酮组在此基础上加用艾司氯胺酮0.25 mg/kg;术中根据患者反应持续泵注瑞芬太尼0.25~4.00μg/(kg·min)和丙泊酚4~6 mg/(kg·h)。记录苏醒期呛咳程度和发生率,记录麻醉前、麻醉诱导后、超声支气管镜进入声门时、穿刺时和苏醒即刻的平均动脉压和心率,记录检查时间、苏醒时间、拔管时间及不良反应发生情况。结果:艾司氯胺酮组苏醒期呛咳程度及发生率均低于对照组(P<0.05);艾司氯胺酮组平均动脉压和心率波动幅度均小于对照组(P<0.05);艾司氯胺酮组低血压、心动过缓发生率低于对照组(P<0.05);两组检查时间、苏醒时间、拔管时间及不良反应发生率(包括心动过速、头晕、躁动、视力模糊)比较,差异均无统计学意义(P>0.05)。结论:丙泊酚复合低剂量艾司氯胺酮能降低无痛EBUS检查苏醒期呛咳的发生,且血流动力学更稳定。 展开更多
关键词 低剂量艾司氯胺酮 超声支气管镜 呛咳
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胸部CT图像质量评价与辐射剂量的临床应用研究 被引量:1
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作者 刘铁 李艳艳 +1 位作者 李鹏 王健 《影像技术》 CAS 2024年第1期19-23,38,共6页
目的:归纳和分析影响胸部CT图像质量的因素,进一步对照分析常规剂量组和低剂量组两组图像质量有无差异,以论证胸部CT低剂量检查的可行性。方法:选取150例胸部CT查体的患者,A组为常规剂量组,管电压120kV,管电流自动调节;B组为低剂量组,... 目的:归纳和分析影响胸部CT图像质量的因素,进一步对照分析常规剂量组和低剂量组两组图像质量有无差异,以论证胸部CT低剂量检查的可行性。方法:选取150例胸部CT查体的患者,A组为常规剂量组,管电压120kV,管电流自动调节;B组为低剂量组,管电压100kV,管电流自动调节。参照胸部CT的图像质量评价标准对常规剂量组和低剂量组图像质量进一步作出主观评价。对辐射剂量、信噪比等客观数据进行统计学处理,以P<0.05为差异有统计学意义。并与主观评价相比较。结果:主、客观评价两组图像质量均无统计学意义,A组辐射剂量与B组辐射剂量有统计学意义。结论:影响图像质量的因素包括患者的因素、设备的因素以及操作者的因素,胸部CT采用100kV低剂量检查可以作为常规扫描方案,获得的图像可以满足影像诊断的要求,具有可行性。 展开更多
关键词 胸部 计算机X线摄影 体层成像 图像质量 低剂量
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小剂量利妥昔单抗联合甲泼尼龙序贯治疗视神经脊髓炎谱系疾病疗效观察 被引量:1
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作者 辜忠灵 甘秀红 丁秀英 《中国药业》 CAS 2024年第2期90-93,共4页
目的探讨小剂量利妥昔单抗联合甲泼尼龙序贯治疗视神经脊髓炎谱系疾病(NMOSD)的临床疗效。方法选取医院2017年1月至2020年6月收治的NMOSD患者112例,随机分为观察组和对照组,各56例。两组患者均予注射用甲泼尼龙琥珀酸钠静脉冲击治疗(100... 目的探讨小剂量利妥昔单抗联合甲泼尼龙序贯治疗视神经脊髓炎谱系疾病(NMOSD)的临床疗效。方法选取医院2017年1月至2020年6月收治的NMOSD患者112例,随机分为观察组和对照组,各56例。两组患者均予注射用甲泼尼龙琥珀酸钠静脉冲击治疗(1000μg/d)3~5 d,逐渐减至125 mg/d,后改为口服甲泼尼龙片48 mg/d(继续减量至4 mg/d维持或停用);观察组患者加用利妥昔单抗注射液100 mg静脉滴注,每周1次,连续治疗4周,6~12个月重复使用。结果治疗后,观察组患者年复发率、扩展残疾状态量表(EDSS)评分均显著低于对照组(P<0.05),外周血T淋巴细胞CD_(3)^(+)和CD_(4)^(+)水平及CD_(4)^(+)/CD_(8)^(+)均显著高于对照组(P<0.05),血清白细胞介素6(IL-6)、白细胞介素17(IL-17)及肿瘤坏死因子-α(TNF-α)水平均显著低于对照组(P<0.05)。两组患者治疗后的天门冬氨酸氨基转移酶、丙氨酸氨基转移酶、血尿素氮、血清肌酐水平均无显著改变(P>0.05)。观察组与对照组不良反应发生率相当(7.14%比12.50%,P>0.05)。结论小剂量利妥昔单抗联合甲泼尼龙序贯治疗NMOSD,能有效改善患者的病情及机体炎症状况,提高免疫功能。 展开更多
关键词 视神经脊髓炎谱系疾病 利妥昔单抗 小剂量 甲泼尼龙 序贯治疗 免疫功能 炎性因子:临床疗效
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阿托品联合其他干预措施在近视防控中的研究进展
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作者 张毅 崔亚晨 +1 位作者 闫瑾 李树茂 《中国现代药物应用》 2024年第1期172-174,共3页
本文综述了近视的发生发展机制和对应的治疗策略,重点阐述了应用阿托品联合其他干预措施治疗近视的作用机制及研究进展,并通过比较各种治疗方法的优缺点,提供更安全、有效的治疗方案,以便更好地推动近视治疗的发展。
关键词 低浓度阿托品 联合干预 近视
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深度学习迭代重建算法优化儿童头颅CT图像噪声和图像纹理的可行性
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作者 田宏伟 彭芸 +4 位作者 刘道永 李昊岩 刘勇 洪天予 孙记航 《中国医学影像学杂志》 CSCD 北大核心 2024年第2期193-198,共6页
目的评价深度学习迭代重建(DLIR)算法与常规自适应迭代重建(ASIR-V)算法对儿童头颅外伤CT图像噪声和图像纹理的优化程度及图像显示效果的差异。资料与方法回顾性选取2020年12月7—11日首都医科大学附属北京儿童医院影像中心80例儿童头颅... 目的评价深度学习迭代重建(DLIR)算法与常规自适应迭代重建(ASIR-V)算法对儿童头颅外伤CT图像噪声和图像纹理的优化程度及图像显示效果的差异。资料与方法回顾性选取2020年12月7—11日首都医科大学附属北京儿童医院影像中心80例儿童头颅CT,扫描方案为低辐射剂量轴扫,电压120 kV,电流150~220 mA。将得到的原始数据重建为5 mm厚层与0.625 mm薄层的脑窗、骨窗图像,分别重建为50%ASIR-V、高权重DLIR图像(DL-H),共8组图像。应用4分制主观评价脑沟脑室、脑灰白质与颅骨显示情况,并统计各组图像的病变数量;客观评价测量基底节层面的灰质和白质的CT值和噪声值,并计算对比噪声比,同时在同层面测量模糊程度指数,比较两种图像重建方法的差异。结果相较于50%ASIR-V图像,2种层厚的DL-H均可以提升脑沟脑室、脑实质显示能力(W=5.5~22.2,P均<0.05),5 mm的50%ASIR-V与0.625 mm的DL-H图像脑沟脑室、脑实质显示能力差异无统计学意义(W=0.9、2.0,P=0.32、0.05)。骨质显示能力方面,所有图像均可以达到满分4.0分。5 mm的50%ASIR-V与DL-H图像均可以在80例患者中发现共35处病变,包括出血病变12处,颅内积气1处,骨折9处,头皮软组织肿胀13处。客观评分方面,DL-H图像噪声低于50%ASIR-V图像(t=21.4~35.7,P均<0.05),0.625 mm的DL-H与5 mm的50%ASIR-V图像噪声及对比噪声比差异无统计学意义(t=1.7~2.2,P均≥0.05)。模糊程度指数显示DL-H优于50%ASIR-V图像(t=6.1、10.0,P均<0.05),0.625 mm的DL-H与5 mm的50%ASIR-V模糊程度指数差异无统计学意义(t=2.6,P=0.28)。结论DLIR可以降低图像噪声,改善图像纹理,整体提升儿童头颅外伤CT图像质量,0.625 mm的DL-H图像质量接近5 mm的50%ASIR-V图像,可以达到诊断要求,使进一步降低儿童头颅外伤的辐射剂量成为可能。 展开更多
关键词 体层摄影术 X线计算机 头颅 儿童 低剂量 深度学习
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Trench型N-Channel MOSFET低剂量率效应研究
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作者 徐海铭 唐新宇 +4 位作者 徐政 廖远宝 张庆东 谢儒彬 洪根深 《微电子学与计算机》 2024年第5期134-139,共6页
基于抗辐射100V Trench型N-Channel MOSFET开展了不同剂量率的总剂量辐射实验并进行了分析,创新性提出了器件随低剂量率累积以及不同偏置状态下的变化趋势和机理,给出了器件实验前后的转移曲线和直流参数,进行了二维数值仿真比较,证明... 基于抗辐射100V Trench型N-Channel MOSFET开展了不同剂量率的总剂量辐射实验并进行了分析,创新性提出了器件随低剂量率累积以及不同偏置状态下的变化趋势和机理,给出了器件实验前后的转移曲线和直流参数,进行了二维数值仿真比较,证明了实验和仿真的一致性。研究表明:随高剂量率的剂量增加,器件阈值电压(V_(TH))发生了明显负向漂移现象,导通电阻(R_(DSON))出现5%左右的降低,击穿电压(BV_(DS))保持基本不变;低剂量率下总剂量效应与高剂量率有明显不同,阈值电压漂移量减小,同时出现正向漂移现象;此时导通电阻(R_(DSON))和击穿电压(BV_(DS))较高剂量率变化量进一步下降。研究认为,低剂量率下器件界面缺陷电荷增加变多,使得阈值电压的漂移方向发生改变,同时低剂量率实验周期是高剂量率的500倍,退火效应也较高剂量率的明显,导致器件参数辐射前后差异性减小。 展开更多
关键词 槽型场效应管 总剂量电离效应 阈值漂移 低剂量率
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小剂量阿司匹林对子痫前期患者胎盘自噬水平的影响
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作者 葛榕 陈品玲 +4 位作者 郑琳 李蕊 杨茵 辛长征 林靓 《临床合理用药杂志》 2024年第16期38-40,44,共4页
目的 观察小剂量阿司匹林对子痫前期(PE)患者胎盘自噬水平的影响。方法 选择2021年1月—2023年6月于福建省立医院预防性服用小剂量阿司匹林的住院分娩PE患者21例作为阿司匹林组,同期未预防性服用阿司匹林的住院分娩PE患者21例作为对照组... 目的 观察小剂量阿司匹林对子痫前期(PE)患者胎盘自噬水平的影响。方法 选择2021年1月—2023年6月于福建省立医院预防性服用小剂量阿司匹林的住院分娩PE患者21例作为阿司匹林组,同期未预防性服用阿司匹林的住院分娩PE患者21例作为对照组,分别采用免疫组化和Real-time PCR检测胎盘自噬标记蛋白Beclin1和LC3B的表达。比较2组患者24 h尿蛋白定量及胎盘组织Beclin1和LC3B蛋白表达水平。结果 阿司匹林组24 h尿蛋白定量为(0.37±0.22)g,低于对照组的(0.95±0.78)g,组间差异显著(t=3.280,P=0.003);阿司匹林组胎盘组织Beclin1和LC3B蛋白表达水平均低于对照组(P<0.01);阿司匹林组胎盘组织Beclin1和LC3B的mRNA表达水平均低于对照组(P<0.01)。结论 小剂量阿司匹林能降低PE患者蛋白尿和胎盘自噬水平,可能与小剂量阿司匹林可有效预防PE有关。 展开更多
关键词 子痫前期 阿司匹林 小剂量 胎盘自噬 血管内皮功能
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基于患者身材的影像采集参数优化与冠状动脉造影低剂量化的相关性分析
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作者 钱海 张玉琴 +1 位作者 楼钶楠 胡德兴 《中国介入心脏病学杂志》 CSCD 2024年第4期191-196,共6页
目的探讨影像采集参数优化与冠状动脉造影辐射剂量和影像质量的相关性。方法选择2022年1月至2024月1月于宁波市医疗中心李惠利医院择期行经皮冠状动脉造影患者60例,采集患者的基本信息和身材数据,根据身体质量指数(BMI)值分为3个组,各BM... 目的探讨影像采集参数优化与冠状动脉造影辐射剂量和影像质量的相关性。方法选择2022年1月至2024月1月于宁波市医疗中心李惠利医院择期行经皮冠状动脉造影患者60例,采集患者的基本信息和身材数据,根据身体质量指数(BMI)值分为3个组,各BMI组患者随机分入常规模式组(冠状动脉模式采集影像:Cardiac Left Coronary,15帧/秒)和优化模式组(电生理模式采集影像:Cardiac EP,7.5帧/秒),收集辐射剂量数据,并根据影像质量评分表评估影像质量。两组间比较采用独立样本t检验、Mann-Whitney U检验,多组间比较采用单因素方差分析,相关性采用Pearson相关分析。结果患者BMI值越高,胸围越大,辐射剂量越高,呈正线性相关;各BMI组内,优化模式组的各项辐射剂量数据(各类型剂量面积乘积、空气比释动能及胸部皮肤剂量)均低于常规模式组(均P<0.05,降低比率48.95%~70.59%),两组间的影像质量评分差异无统计学意义(P>0.05),均符合手术要求。结论经皮冠状动脉造影的辐射剂量受患者身材、影像采集参数、曝光时长等诸多因素的综合影响,通过优化影像采集参数可在保证影像质量的同时实现辐射低剂量化,减少患者和术者的辐射危害。 展开更多
关键词 冠状动脉造影 影像采集 低剂量 影像质量
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